CVE-2026-4687
Modified
Modified - Updated After Analysis
Sandbox Escape in Firefox Telemetry Due to Boundary Error
Vulnerability report for CVE-2026-4687, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-03-24
Last updated on: 2026-06-30
Assigner: Mozilla Corporation
Description
Description
Sandbox escape due to incorrect boundary conditions in the Telemetry component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| mozilla | firefox | to 149.0 (exc) |
| mozilla | firefox | to 115.34.0 (exc) |
| mozilla | firefox | From 128.0 (inc) to 140.9.0 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-754 | The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product. |
| CWE-501 | The product mixes trusted and untrusted data in the same data structure or structured message. |
| CWE-120 | The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer. |
